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1.

Aim

To characterize the urinary metabolomic fingerprint and multi-metabolite signature associated with type 2 diabetes (T2D), and to classify the population into metabotypes related to T2D.

Methods

A metabolomics analysis using the 1H-NMR-based, non-targeted metabolomic approach was conducted to determine the urinary metabolomic fingerprint of T2D compared with non-T2D participants in the PREDIMED trial. The discriminant metabolite fingerprint was subjected to logistic regression analysis and ROC analyses to establish and to assess the multi-metabolite signature of T2D prevalence, respectively. Metabotypes associated with T2D were identified using the k-means algorithm.

Results

A total of 33 metabolites were significantly different (P < 0.05) between T2D and non-T2D participants. The multi-metabolite signature of T2D comprised high levels of methylsuccinate, alanine, dimethylglycine and guanidoacetate, and reduced levels of glutamine, methylguanidine, 3-hydroxymandelate and hippurate, and had a 96.4% AUC, which was higher than the metabolites on their own and glucose. Amino-acid and carbohydrate metabolism were the main metabolic alterations in T2D, and various metabotypes were identified in the studied population. Among T2D participants, those with a metabotype of higher levels of phenylalanine, phenylacetylglutamine, p-cresol and acetoacetate had significantly higher levels of plasma glucose.

Conclusion

The multi-metabolite signature of T2D highlights the altered metabolic fingerprint associated mainly with amino-acid, carbohydrate and microbiota metabolism. Metabotypes identified in this patient population could be related to higher risk of long-term cardiovascular events and therefore require further studies. Metabolomics is a useful tool for elucidating the metabolic complexity and interindividual variation in T2D towards the development of stratified precision nutrition and medicine.Trial registration at www.controlled-trials.com: ISRCTN35739639.  相似文献   
2.
建立了测定盐酸美金刚片含量的气相色谱(GC)方法。方法采用Agilent DB-225 (30m*0.53mm,1.0μm)毛细管色谱柱,以氮气为载气,流速5mL.min-1,柱温:110℃,进样口温度:250℃,进样量:2.0μL。火焰离子化检测器(FID),检测器温度:250℃。以盐酸金刚乙胺作为内标物测定盐酸美金刚片的含量。盐酸美金刚在0.157 8mg.mL-1~0.480 6mg.mL-1范围内与峰面积呈现良好的线性关系(r=0.999 0)。所建立的方法准确、回收率较为理想,可用于盐酸美金刚片含量的测定。  相似文献   
3.
Matrix solid-phase dispersion (MSPD) is a simple and cheap sample preparation procedure allowing for the reduction of organic solvent consumption, exclusion of sample component degradation, improvement of extraction efficiency and selectivity, elimination of additional sample clean-up and pre-concentration step before chromatographic analysis.  相似文献   
4.
Rev7™ is an indigestible gum polymer used for the manufacturing of chewing gum. It allows for the formulation of chewing gum with low adhesion; thus can be readily removed from surfaces such as sidewalks, clothing, carpets and furniture. In a toxicological safety assessment, Rev7™ was found to be non-mutagenic in the AMES assay. The highest concentration tested in a mouse lymphoma thymidine kinase locus gene mutation assay induced a slight but biologically relevant increase in mutations under non-metabolic activation conditions after 24 h. Because of this finding, a mouse micronucleus assay was performed, and the test article was found to be negative for inducing chromosomal damage. A 28-day repeated oral toxicity study resulted in a NOAEL of 80,000 ppm; the highest concentration tested. Rev7™ was found to be free from contaminants such as heavy metals, monomers, and solvents. Lastly, Rev7™ did not demonstrate skin-sensitizing properties in the murine local lymph node assay.  相似文献   
5.
Minthostachys verticillata (peperina) is an aromatic and medicinal plant with several uses and ethnobotanical properties. Numerous studies have demonstrated that its essential oil (Mv-EO) presents antimicrobial capacity and shows immunomodulating and anti-allergic properties in human cell lines. Thus, the goal of this study was to investigate the main chemical composition, analyzed by GC–FID, and the cyto-genotoxic effects of Mv-EO, using Vero cells, human PBMCs and mice bone marrow cells. The Mv-EO was rich in pulegone 60.5% and menthone 18.2%. Our results clearly show that Mv-EO is not cyto-genotoxic in vitro nor in vivo. It not induced cytotoxic effects, as indicated by trypan blue dye exclusion and NRU assays both in Vero cells and human PBMCs. In addition, Mv-EO (100–1000 μg/mL) not induced apoptotic effects on human PBMCs, as indicated by Hoechst staining and DNA fragmentation analysis by agarose gel electrophoresis. The in vivo assay showed that Mv-EO (25–500 mg/kg) not increased the frequency of micronucleus in bone marrow cells of mice. Further, the ratio of polychromatic/normochromatic erythrocytes was not modified. These findings suggest that Mv-EO appears to be safe as a therapeutic agent.  相似文献   
6.
A sub-critical chromatography (SubWC) with water as mobile phase and FID detection system is employed to separate several alcohols with high or medium polarity, with pure water as the eluent. The flow rate gets up to 50 μ1-min^-1 for packed column (1 mm i.d.) and 70 μ1-min^-1 for capillary (50 μm i.d.). Increasing the temperatureup to 140℃, together with temperature programming, markedly improves the separation and peak shapes within short analysis time. Sub-critical state is guaranteed.  相似文献   
7.
邱丰和  刘力  罗毅  卢涌泉 《药学学报》1996,31(3):205-208
报道了一种能同时快速测定血浆中酸性和碱性药物的固相萃取毛细管气相色谱法。在自制的并联双柱萃取装置上,两柱可在不同的pH下操作,分别提取酸性和碱性药物。通过对6类8种酸性和碱性药物的定性和定量实验表明,该法快速、灵敏。  相似文献   
8.

Background

Functional iron deficiency (FID) is an independent risk factor for poor outcome in advanced heart failure with reduced EF, but its role in heart failure with preserved EF (HFPEF) remains unclear. We aimed to investigate the impact of FID on cardiac performance determined by pressure–volume loop analysis in HFPEF.

Methods

26 HFPEF patients who showed an increase in LV stiffness by pressure–volume (PV) loop analysis obtained by conductance-catheterization, performed exercise testing, echocardiographic examination including tissue Doppler and determination of iron metabolism: serum iron, ferritin and transferrin saturation. HFPEF patients who provided ferritin < 100 μg/l or ferritin of 100–299 μg/l in combination with transferrin saturation < 20% were defined as having FID. In 14 patients the expression of transferrin receptor was determined from available endomyocardial biopsies.

Results

Fifteen out of 26 HFPEF patients showed FID without anemia. Compared to control subjects and HFPEF patients without FID, HFPEF patients with FID showed an up-regulation of the myocardial transferrin receptor expression (p < 0.05). No differences between HFPEF patients with and without iron deficiency were found in heart dimensions, systolic and diastolic function obtained by PV-loop and echocardiography analysis. According to the linear regression analysis, LV stiffness was correlated with peak oxygen uptake (r = − 0.636, p < 0.001) but not with the ferritin level or transferrin saturation. No relation was found between FID and exercise capacity. The association of LV stiffness with exercise performance was independent from the level of iron deficiency.

Conclusion

In non-anemic HFPEF patients, cardiac dysfunction and impaired exercise capacity occur independently of FID.  相似文献   
9.
Objectives The aims of this study were to establish the antimicrobial potential of Hofmeisteria schaffneri essential oil and its chemical composition. Methods The essential oils of Hofmeisteria schaffneri harvested at flowering (batches I and IV) and non‐flowering (batches II and III) seasons were prepared by hydrodistillation and analysed by GC and GC‐MS. The aqueous and organic (CH2Cl2‐MeOH 1 : 1) extracts were prepared by using infusion and maceration techniques, respectively. The in‐vitro antimicrobial activity of the preparations and compounds against Candida albicans and some bacteria (Gram‐negative and Gram‐positive) was assessed using the broth dilution method in 96‐microplate wells. Key findings Forty‐four compounds, representing ~90% of the total constituents, were identified in the essential oil of Hofmeisteria schaffneri collected in flowering (batches I and IV) and non‐flowering (batches II and III) seasons. In all cases, several thymol analogues were the major components of the oils (~65%); some small differences in the relative proportions of these constituents were observed. The infusion exhibited an antibacterial activity against Staphylococcus aureus and Bacillus subtilis, with a MIC value of 64 µg/ml in each case. The essential oil batches were active against Staphylococcus aureus, with MIC ranging from 48 to 192 µg/ml. They were, however, inactive against Gram‐negative bacteria, including Pseudomonas aeruginosa, Escherichia coli and Salmonella typhi (MIC > 1024 µg/ml). On the other hand, the infusion of the plant as well as the oil from batch I displayed anti‐Candida albicans activity, with MIC of 128 and 192 µg/ml, respectively. Finally, the organic extract did not displayed significant activity against the tested microorganisms (MIC ≥ 1024 µg/ml). Some of the compounds isolated from the plant were also tested. Compounds 8 and 38, which were present in the essential oils, displayed the best antibacterial effect against Gram‐positive bacteria (MIC ranging between 32 and 64 µg/ml). Compounds 6 (present in the infusion) and 10 (present in all preparations) showed higher activity against the yeast (MIC = 128 µg/ml) than the remaining compounds, with MIC values ranging from 256 to 512 µg/ml. Conclusions The composition and antimicrobial activity of the oils changed slightly from flowering to non‐flowering seasons. The results of the present investigation provide in‐vitro scientific support for the use of the plant against skin infections in Mexican folk medicine.  相似文献   
10.
[目的]建立同时分析《GB/T 5749-2006生活饮用水卫生标准》[1]中多种挥发性有机物组分的分析方法。[方法]采用吹扫捕集方法富集待测组分,用气相色谱FID检测器内标方法定量分析。[结果]28种挥发性有机物可以同时进行测定,分析方法的线性范围:芳烃及其衍生物在4~40μg/L,卤代烷烃在20~200μg/L。各组分回收率均在95%~101%之间。各组分变异系数多数5%。[结论]该方法同时分析生活饮用水28种挥发性有机物,除四氯化碳(检测下限不能满足)外其余组分完全满足对《GB/T 5749-2006生活饮用水卫生标准》挥发性有机物评价的需求。  相似文献   
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